By Mohammed Abbas and Alexander Dziadosz
RAS LANUF, Libya (Reuters) - Muammar Gaddafi's forces launched a fresh bombardment of the eastern Libyan oil town of Ras Lanuf on Thursday, rebels and witnesses said.
Bombs or missiles landed a few km (miles) from Ras Lanuf oil refinery and close to a building of the Libyan Emirates Oil Refinery Company building, a Reuters witness said.
"One bomb landed on a civilian house in Ras Lanuf," rebel fighter Izeddine Sheikhy told Reuters.
He said the bombardment seemed to have come from the direction of the sea. This could not be confirmed and there were no further details of the attack. A warplane was circling over Ras Lanuf, the Reuters witness said.
Earlier, rebels fired rockets out to sea after reports that Libyan gunboats in the Mediterranean may have attacked rebel positions on the front line in the oil-producing east.
A counter-offensive by forces loyal to Gaddafi has halted the rebels' advance along Libya's eastern coast, where they have been forced to withdraw from the strategic town of Bin Jawad after coming under heavy fire.
"We came into Bin Jawad but gunboats fired on us so we withdrew," fighter Adel Yahya said on Wednesday night.
Rebel colonel Bashir Abdul Qadr could not confirm whether naval vessels had been used but said: "We had bombing from the direction of the sea."
Rebel fighters said on Thursday they were based on the outskirts of Bin Jawad and near the oil complex of Es Sider, also known as Sidrah, which suffered a direct hit in Wednesday's fighting, sending black smoke and flames belching into the sky.
Rebels, who have taken swathes of territory in the east and who are becoming better organized, were stopped from taking the coastal road west to the prized target of Sirte, Gaddafi's hometown, by tanks and warplanes.
In the push from Libya's second city Benghazi, where the uprising started and where the rebels now have their headquarters, the rebel army of defectors and young volunteers have captured the oil towns of Brega and Ras Lanuf.
Dr Gebril Hewadi of the Benghazi medical management committee told Reuters television at least 400 people had been killed in eastern Libya since clashes began there on February 17, with many corpses yet to be recovered from bomb sites.
Libyan state television broadcast what it said was a conversation between the U.S. ambassador, who was speaking in English through a translator, and Omar Hariri, the military representative of the rebel National Libyan Council, whom it described as an "agent" and "lackey."
The ambassador asked how rebel headquarters could keep up regular contact with fighters, what contacts Hariri had with towns like Zawiyah and what forces he commanded. Hariri said he was in charge of forces in east Libya.
An American envoy left Cairo on Thursday on a plane to Salum on Egypt's border with Libya, a Cairo airport official said. The official cited U.S. embassy staff as saying he would be following Libyan developments at first hand.
Two U.S. military planes arrived in Cairo from Jerba in Tunisia carrying 150 Egyptians who had been working in Libya, the airport official said. Three EgyptAir flights also arrived carrying 379 Egyptians.
The United States has sent planes in recent days to repatriate Egyptians after they fled to Tunisia from Libya.
(Writing by Peter Millership; editing by Andrew Roche)